Means for supporting and insulating high-tension electrodes in electrical precipitation apparatus



H. V-. WELCH.

MEANS FOR SUPPORTING AND INSULATING HIGH TENSION ELECTRODES IN ELECTRICAL PRECIPITATION APPARATUS.

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MEANS FOR SUPPORTING AND INSULATING HIGH TENSION ELECTRODES IN ELECTRICAL PRECIPITATION APPARATUS.

I I I 3,9 I I APPLICATION FILED JAN. 27, I919- Patented Se It. 20,1921.

H 2 SHEETSSHEET 2. INC .4. TE; n I 34 36 l I 37 I 1 ar L, '/s' INVENTOR'. Harry V. Welch UNITED STATES PATENT OFFICE.

HARRY WELCH, OF ANGELES, CALIFORNIA, ASSIGNOR TO INTERNATIONAL PRECIPITATION COHPANY, 01 LOS ANGELES, CALIFORNIA, A CORPORATION OI CALIFORNIA.

MEANS FOR SUPPORTING AND INSULATING vI-IIIIGH-EIIENSION ELECTRODES IN ELEC- TRICAL PRECIIITATION APPARATUS.

Specification of Letters Patent.-

Patented Sept. 20, 1921.

Application filed January 27, 1919. A Serial No. 278,829.

contains material such as acid fume, carbon articles, or other suspended material which is liable to collect on the insulators and reduce the insulating efiiciency thereof.

The main object of the present invention is to provide means for protecting the insulators of such apparatus in such manner as to prevent collection of injurious deposits thereon.

The accompanying drawings illustrate embodiments of my invention, and referririg thereto:

igure 1 is a partly sectlonal slde elevation of a precipitating apparatus provided with my invention;

Fig. 2 is a transverse section thereof on line 2-2 in Fig. 1, with the right hand portion thereof broken to show the insulator in section;

Fig. 3 is a vertical section of one of the insulators with its protecting means;

Figs. 4 to 6, inclusive, are vertical'sections of modified forms of the insulator.

Referring to Figs. 1 and 2, the precipitator therein shown comprises a casing 1 having inlet and outlet conduits 2 and 2' ada ted to pass the gas to be treated through said casmg, said casing having also means 3 at the bottom portion thereof for collecting and removing the preci itated material. My invention is particu arly applicable in connection with the preci itation of acid fumes and when so applied: the collectin and removing means 3 may consist, as s own, of funnels at the bottom of the casing 1, connected with suitable conduits 3, for drawing off the collected liquid. .Suitable collecting electrodes, such as vertical plates 4, are provided within the casing 1, being for example, hung from the top plate 1' o the casing in planes parallel with the direction of the flow of gas through the casin The discharge electrode system of t e precipitator comprises a series of rows of discharge electrodes formed, for exam le, as wires 5 hung from horizontal frame ars 6 mounted on a high tension frame supported by insulating means as hereinafter described, said wires being tensioned by means and being arranged in rows between the respective collecting electrode plates 4.

The high tension frame may comprise vertical bars 7, connected by upper horizontal bars 8 and'8', said bars 8 supporting members 6 aforesaid, and lower bars 9 forming a lower frame through which the respective discharge electrodes pass so as to space and retain said electrodes in proper position.

The vertical bars 7 are supported at their upper ends on horizontal beams 10, mounted on the insulators 11. Each insulator 11 is provided with means for maintaining a current or stream of clean gas in contact therewith and flowing in such direction as to prevent access of suspended material to the surfaces of the insulator. The form of insulator shown in Figs. 1 to 3 consist of a hollow member of insulating material, mounted at its lower end on a tubular support 12, communicating with a lateral pipe 13 through which clean air may be supplied to the interior of the insulator, said insulator having openings 14 through which said clean air ma pass to the outside of said insulator and emg provided with) a hood 15,

mounted on top of the insulator and havin a .depending apron 15 extending aroun the same so as to deflect the air in a stream assing down around the insulator. ower end of the. apron 15' is preferably formed with an inwardly projecting ridge 16 so as to provide a constricted passage between it and the tubular support 12. The insulator 11 may be of an suitable material, for example, porcelain, glass or uartz, and may be of any suitable form, an the hood 15 may be of metal or other suitable material.

The insulator is preferably inclosed within an insulator box or casing 17 on top of the main casing 1, said insulator box communi- The ofsuitable weights 5' at their lower ends through these vertical tubes 18 so that the only communication between the insulator box and the treater casing is through these tubes and the tendency of the finely divided suspended material to diffuse into the insulator box is therefore resisted and overcome to a large extent by the stead flow'of gas downwardly through these tu es; however, in case of acid fume, or finely divided carbon, and some other materials, the tendenc for difi'usion is so great that some ofsuc material will inevitably enter the insulator chambers, this bein particularly the case while there is liability to fluctation of pressure with the result that there is a tendency occasionally to reversal of gas stream through the communicating tubes'18. The fact that the clean gas from outside is continually passing down around the insulator 11 from the openings 14 and within the hood 15 insures that any suspended material that may enter the insulator casing or chamber will be kept away from the surfaces of the insulator, and the construction of the passage at the lower end of the hood also conduces to this efiect.

In order to facilitate access to the insulator in case of accident, or in the possible eventuality of its requiring cleaning from time to time, the hood 15, or a portion thereof, may be made removable, as shown more particularly in Fig. 3, said hood comprising a cylindrical apron 'or wall 15', detachably mounted on the top plate 19, which rests on the insulator 11. Any suitable means may be provided for detachably holding said cylindrical apron on the top plate, for example, swinging ,lugs 21 mounted on the member 15' and passing throughnotches 22 on the top member 19, said lugs being rovided with nuts 23, screwing thereon an en- 1gzging with the top plate to hold the memr 15' firmly, in position. A In case gases carrying acid fume are being treated, it is desirable to provide means for heating the protective gas stream for the insulator and for this purpose a heater, for

example, an electric heater 25, may be provided within a box 26, communicating with the inlet pipe 13 and connected to the bottom of the tubular member 12, said electric heater being supplied with electric current through suitable connections 27. This heating action aids in the circulation of the gas and tends to keep the insulator body warm and dry in passing upwardly through the same and in passing downwardly onthe outside of same between the insulator body and the hood, thereby insuring the eifectiveness of the insulator in cases where there is liability of deposition of fume or moisture on the insulator.

In electrical precipitators operating on gases of the above described character, the introduction of the high tension lead to the high tension electrodes is somewhat of a problem on account of'the difiiculty of insulating the same where it passes through the treater casing, as any insulation provided at such point is liable to become coated with the acid fume, or conductin deposit, in such manner as to nullify its insulating effect. I provide for overcoming this ifiiculty by utilizing the insulator construction above set forth in 'such a manner as to bring in the high tension lead connection through the insulator support so that the same provisions which maintain the insulator clean and effective also protect the high tension lead. For this purpose the high tension circuit wire 32 may be connected to the top 19 of the hood resting on the insulator 11 and may pass down through through aninsulating disk or plate 29, closin the outer end of said tubular member 28. .n order to reduce the size of the tube that is necessary to prevent jump or arcing of the high tension current from the wire 32 to the tubular member 12, said wire may be covered with an insulating sheath 31.

In case the insulation is of such ma nitude that it becomes of importance to eliminate side strains on the insulators, the constructions shown in Fi s. 1 and 2 are of advantage in that the top earns 10 extend over the insulators and have the vertical frame bars 7 hung at their ends so that the weight of the high tension system is imparted through the beams 10 directly downward on the insulators, notwithstanding the fact that the vertical bars 7 are ofiset from the in- With such a construction, it is,

sulators.

referred to inclose the horizontal beams 10, or example, by tubular casings 33, connecting the insulator boxes 17 for the respectivecated cone, as shown in this figure. This figure also illustrates the construction of the insulator boxes 17 in snch manner that it overhangs or extends out from the main casin l and vertical tube '12 extends downward y through the bottom of the insulator boxes so as to-communicate at 13' with the outer air. The wire 32 for conducting high tension current to the high tension system is shown in this case as extending vertically through the tube 12 being connected. at its upper end to thehood 35 and passing at .its lower end through an insulating plate 29 at the bottom of the tube 12'.

Another modification is shown in Fig. 5 wherein the insulator indicated at 38, is solid, consisting, for example, of a porcelain insulator of well known type, mounted on the upper end of the air inlet tube 39 and supporting the hood 40. Said air inlet tube is provided with openings 41, which communicate with a space within the hood 40 so that air passing upwardly through the inlet tube will flow downwardly through the hood.

' In the modification shown in Fig. 6, the insulator 43 is mounted by a spider 44 on the u per end of an air inlet tube 45 and the high tension wire 46 extends upwardly through said tube and laterally between the top 0 heat with the hood 48.

In each of the described embodiments of the invention, the operation of the electrical precipitator in usual manner involves the passage of gases containing suspended ma-.

terial, for example, acid fume, through the precipitator chamber 1, such ases being subjected to the action of electric fields between the discharge and collecting electrode systems in such manner as to cause precipitation of suspended material on the collecting electrodes in well known manner. The operation is preferably carried out by the use of a high tension unidirectional current of suitable potential difierence, the wire 32 leading to the high tension system being connected toany suitable source of high tension current, for example, to a high tension rectifier and the casing 1 and collecting electrodes 4 being grounded so as to complete the connection in usual manner.

Diffusion of the suspended material in the gas from the main chamber 1 to the insulator boxes 17 is minimized by the constricting tubes 18 and the continual current of air forced or drawn in through the tubes 13 and 12 and their openings 14 and then assing downwardly in the hood 11 insures t at any suspended material that may find its wayinto the insulator boxes will be kept away from the insulators therein. The current of air necessary for this operation may be maintained by the draft through the precipitator, such draft being induced by connecthe tube'and the insulator 43 to contion to a stack, or otherwise, resulting in a condition .of lower pressure within the treater as compared with the outside air and therefore causing air to be drawn from the outside through tubes 13' and 12 and openings 14 to the insulator chamber and then down throu h the sleeves or tubes 18 to the main cham er 1; if desired, however, this current of clean air may be forcibly supplied to the tube 13 by any suitable means. 11 case of breakage'of an insulator, or of other injury thereto, the same may be readily inspected and repaired by releasing the insulator shield 15 and lowering the same so as to expose the insulator.

What I claim is: 1. An insulator comprising a hollow body of insulating material provided at its lower end with means for admitting clean gas thereto and with outlet means at its upper end and a hood surrounding the insulator and spaced therefrom, said outlet, means opening into the space within said hood for passing clean gas into said space.

2. An insulator comprising an insulating body having a vertical passage provided at its lower end with means for supplying gas thereto and with outlet means at its upper end whereby gas is caused to pass vertically through said lnsulatin body and means for heating said as supplied to said passa e.

3. An insu ator constructed as set orth in claim 2 and comprising in addition a hood extending over and around the insulator and adapted to deflect the current of gas from said outlet means at the upper end of' the insulator downwardly around the insulator.

4. Insulating means for the high tension electrodes of electrical precipitating apparatus, comprising a hollow msulator, supporting means for said insulator having a passage therethrough in communication with the interior of said insulator and a source of clean gas, and a hood surrounding andspaced from said insulator and having a gas-outlet at one end, said hollow insulator having a passage connecting its interior with the space between said insulator and said hood at a point remote from said gas-outlet.

5. Insulating means for the high tension electrodes of electrical precipitating apparatus, comprising a hollow vertical insulator, tubular supporting means for said insulator having a passage therethrough in communication at its upper end with the interior of said insulator and at the other end with a source of clean gas, and an opened-bottom hood surrounding and spaced from said insulator, said hollow insulator having a passage connecting its interior with the upper portion of the space between said insulator and said hood.

6. An insulator for high tension electri- III cal apparatus, consisting of a hollow insulating body, having lateral openings, supporting means for said insulator provided with air supply connections and having a passage communicating with the hollow insulator to supply air thereto, and to cause air to pass outwardly through said openings and a hood mounted on said insulator and surrounding the same to deflect the air issuing from said openings downwardly around said insulator.

7. In combination with a supporting frame for the high tension electrodes in an electrical precipitating apparatus, and with the'inclosingcasing for said electrical precipitator, a plurality of insulators mounted above said casing, horizontal beams mounted on said insulators, said casing having openings in its top and vertical tubes at said openings, vertical suspension bars connected to said supporting frame for the high tension electrodes and hung from said supporting beams and extending through said vertical tubes, and means inclosing said insulators and the horizontal beams mounted thereon.

8. In an electrical precipitating apparatus, the combination with the inclosing casing therefor of an insulator, a hollow support mounted on said casing and supporting said insulator, frame means mounted on said insulator for supportin the high tension electrodes of the electrica precipitator and a conductor extendingwithin said hollow support for said insulatorand connected to the said frame means for su plying high tension current thereto, sald hollow support being providedwith means for conducting clean gas thereinto and with aperture means for passing such gas around the insulator.

In testimony whereof I have hereunto subscribed my name this 14th day of- January, 1919.

HARRY V. WELCH. 

